666
FXUS64 KBRO 090817
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
317 AM CDT Tue Jul 9 2024

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(Today through Wednesday)
Issued at 311 AM CDT Tue Jul 9 2024

A summer time pattern is set to be in place over Deep South Texas
and the Rio Grande Valley. A weakness in the 500mb height pattern
couple with the continued easterly to southeasterly flow will result
in a favorable environment that could see some isolated showers and
thunderstorms develop. With PWATs still over 2 inches and the
steering flow of the atmosphere being weak, storms that do develop
could bring heavy rain and possibly train over an area leading to
some localized flooding. With CAPE values are over 2000 J/kg there
will certainly be some energy in the atmosphere for storms to tap
into.

As for the temperatures, the highs are expected to be in the range
of mid 90s to triple digits. Thanks to all the moisture the heat
indices could even get up to 114. However, if any significant cloud
coverage develops that could actually reduce the expected high
temperatures and the heat indices. Another factor to have consider
is that the elevated heat indices do not persist for a long time. As
such a Special Weather Statement will be issued for the elevated
heat indices. There is still a possibility that a Heat Advisory
would be needed if heat indices do rise early in the afternoon. As
for the low temperatures, they are expected to be in the 70s with a
few places in the low 80s.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 311 AM CDT Tue Jul 9 2024

A broad 500mb trough/weakness persist across Texas through the end
of the workweek in-between anomalous ridging over the western CONUS
and the Bermuda Ridge extending over the eastern Gulf of Mexico.
Farther south an inverted trough (remnants of 96L) moves across
eastern Mexico Wednesday night and Thursday. Sufficient moisture
already in place increases Thursday and Friday with passage of the
inverted trough will combine with the sea breeze and differential
heating maintaining a good chance of daily diurnal showers and
thunderstorms in the forecast. The tropical nature of the Mid July
moisture (Pwats 2-2.25 inches) will be the catalyst for pockets of
heavy efficient rainfall. Any slow moving thunderstorm could produce
a quick one to two inches of rain.

Next weekend into early next week the latest deterministic models
show the mid-level weakness filling in as it drifts west and the
western ridge expands eastward overspreading the southern half of
the CONUS. This should allow for pops to reduce to slight chances.

Temperature trends start off near to slightly below normal Thursday
and Friday with the higher rain chances, so expect highs in the mid
90s and minimums in the mid to upper 70s. Rising temperatures to the
mid 90s to lower 100s (upper 70s to lower 80s for minimums) for the
weekend and early next week can be expected as rain chances trend
lower.


&&

.AVIATION...
(06Z TAFS)
Issued at 1214 AM CDT Tue Jul 9 2024

VFR conditions are expected to persist through the TAF cycle at
all TAF sites. Southeasterly winds are expected to continue while
remaining mostly light. Some low-level clouds are expected to move
through the are, but shouldn`t have an impact on the flight
categories. There is also a possibly of showers and thunderstorms
but confidence isn`t high enough to include in the TAF package.

&&

.MARINE...
Issued at 311 AM CDT Tue Jul 9 2024

Today through Wednesday...Light to moderate onshore flow with low to
moderate seas will result in favorable conditions through
Wednesday.

(Wednesday night through Monday)...Weak surface ridge anchored
over much of the Gulf waters the remainder of the week and into
the weekend provides favorable marine conditions. Light to
occasionally moderate southeast winds and low seas are expected.
Isolated to scattered showers and thunderstorms, some with heavy
rainfall and gusty wind, are expected anytime with the majority
overnight and early morning hours.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             96  79  93  79 /  30  10  60  30
HARLINGEN               97  76  94  75 /  30  10  60  20
MCALLEN                100  79  95  78 /  20  10  50  20
RIO GRANDE CITY        100  79  95  77 /  10  20  40  20
SOUTH PADRE ISLAND      89  82  87  80 /  30  20  60  40
BAYVIEW/PORT ISABEL     93  79  91  77 /  30  10  60  30

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through this evening for TXZ451-454-455.

GM...None.
&&

$$

SHORT TERM...64-Katz
LONG TERM....59-GB
AVIATION...64-Katz